The truth about the chartered surveyor’s best friend, the Protimeter or more commonly known as Damp meters.
Unfortunately, we feel that our hands are tied when it comes to the Damp Meter and writing this blog. We received a very angry call from an owner of a house we surveyed recently saying that she had spoken to her friend who is a chartered surveyor, and they said we had not done a proper job as we did not use a damp meter to test for damp nor did we recommend further investigation. We explained politely that her chartered surveyor friend needs to go back to school. We understand why the damp meter is used so readily by our professional colleagues who are so quick to diagnose rising damp and suggest further investigation by a damp specialist who is a member the property care association etc etc. As it appears it is clearly pushing you onto someone else or pushing the problem onto someone else. The problem comes from the fact that lot surveying companies undertake two to three surveys a day. Can you imagine how much time you will have to inspect and find the cause of every problem in a house in 90 minutes? You can’t. We undertake one survey a day and a maximum of three a week (depending on the size and complexity). Most surveyors need a quick, easy to use tool to check a large area and the protimeter fits well.
Unfortunately, however, moisture meters do not actually measure either moisture or damp. These devices measure electrical conductivity, they then interpret this against the “normal” conductivity of timber (pin mode) or masonry (scan mode), if it is higher then expect it flashes up a higher number and either a yellow light with an “at risk” warning or red with a “wet” warning. This scary red light is then followed by a loud beeping noise to make sure you know you’ve found gold..
It is reasonable to suppose that if the “damp meter” says a wall is wet then you must have a damp problem. So, it must be easy to be a surveyor? Well actually no. Firstly not all timber or all walls are the same. Different woods have different levels of conductivity just as different walls and construction types do. The readings can also be affected by things like timber treatments and wall finishes plus so many other things. It should be noted that electrical resistance type meters cannot be used for measuring dampness in masonry because they give unreliable results in any material other than clean un-treated timber.
Chemical injection of damp proofing is advised in around 5,000 UK weekly – which costs more than £200 million per year – and much of this is because of the widespread misuse of electrical moisture meters. Other types of damp proofing such as electro-osmosis and atmospheric siphons e.g. Wallguard, Schrijver Systeem and Holland Damp Proofing are equally pointless, do not solve the source of damp and apart from destroying the aesthetic of the house can actually increase the passage of moisture into the property thus increasing or creating damp issues.
So, are all surveyors bad and are the damp companies all a major con?
No. Some of the best damp surveyors we know are members of the PCA. Unfortunately, there are some bad members and probably used to be a lot more who have tarnished the name.
But why isn’t my “building Surveyor” able to test for damp and/ or tell me how to solve it. Good question. The answer is time and knowledge, particularly on older buildings. Time because they are hard pushed to get to the next survey and knowledge because they are taught in university how to survey a modern house. They then try to switch this knowledge to a traditional building, and it all comes apart. Something that you must understand with any traditional building is that they are different. Historic buildings are special. A wealth of traditional skills went into their construction. They use different materials and building techniques to modern buildings, and they perform and behave differently.
This simple message has been lost in construction and the mainstream society for a considerable amount time, but gladly we are starting to bring conservation principles back into greater understanding and usage. Traditional, solid wall structures are designed to absorb and release moisture freely, evenly distributing moisture and allowing it to evaporate over a wide area. This mechanism of moisture movement and controlling damp is the largest single reason buildings decline and become damp and defective. We often hear people say that old buildings are damp! Well they weren’t built that way. Something has changed, probably in the last 60 years and we must understand how the building was built, what changes have occurred and are those changes harmonious with the structure or causing issues. Often unbeknown to homeowners who are spending large amounts of money maintaining and improving their homes, they receive bad advice, bad workman and this leads to problems.
If you have a mortgage survey who has found damp, rising damp or damp coming from somewhere, you will find with a mortgage company that they can ask that various sums of money are retained due to dampness. We have seen on most of these that they recommend you consult a damp proof specialist such as a member of the BWPDA (The British Wood Preserving & Damp-proofing Association) which are part of the Property Care Association. Why they don’t recommend a member of the RICs, we don’t know. Or just an independent maybe?
The RICS (Royal Institution of Chartered Surveyors) is a professional body that represents the public’s interests first as it is chartered and upholds standards for the chartered surveyors within it.
Some of the best surveyors we have met are not members of the RICS. True. But at least you know that by instructing a RICS registered firm and surveyor they are accredited, qualified and conform to professional standards and ethics.
Damp Meter! The biggest enemy of Old Houses (in the wrong hands).
So, what do we need to do as surveyors? Firstly, use what God gave you, our eyes, smell and touch. If its damp, guess what it will probably be a bit wet or cold, there may be staining or mould or decay. Often, you can smell damp when you enter a building. We then use a variety of tools to assist us such as Thermal Imaging to highlight any cold bridging or thermal imbalances that may indicate signs or sources of damp. We also use Thermo Hygrometer to measure the atmospheric moisture levels in the property.
What happens if your surveyor finds you have high damp meter readings? If your RICS Surveyor suspects that a property suffers from rising damp, you should book a damp and timber survey and find out what is actually happening, if there is actually damp and if so how to solve the problem long term.
Contact Dave on 07568 513972 or drop me an email at info@smithheritagesurveyors.com for a chat or to find out more. If you’ve had a survey identify rising damp and you’re starting to see the light and don’t want to waste thousands of pounds and trap dampness in your walls, give me call.